Please help with these 3 questions about simplifying square roots...
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Answer:
#2:
To get rid of a radical we multiply the radical by itself, so we multiply [tex]\frac{3}{\sqrt{2}} by \frac{\sqrt{2}}{\sqrt{2}}[/tex]
to get [tex]\frac{3\sqrt{2}}{2}[/tex].
#3:
[tex]\sqrt\frac{2}{5}[/tex] is the same as [tex]\frac{\sqrt{2}}{\sqrt{5}}[/tex] so we multiply by [tex]\frac{\sqrt{5}}{\sqrt{5}}[/tex] so we get [tex]\frac{\sqrt{10}}{5}[/tex].
#4:
We combine like terms to get [tex]-2\sqrt{2} + 4\sqrt{3}[/tex]
Hope this helps!